Conventionally, while a battery of an electronic apparatus, such as a portable telephone, or the like is being charged, various circuits operable by being supplied with electric power from the battery (Hereunder, called main circuits) are charged by the battery.
This causes a problem that a capacity of the battery is reduced in spite of charging the battery, or that a time for charging the battery becomes long.
A technique disclosed, for example, in Patent Reference 1 is involved in conventional techniques made in view of the problems thus mentioned.
Patent Reference 1 discloses a calling apparatus in which a battery is supplied with a charging power from a charger, the calling apparatus comprising: an electric power supplying terminal for directly supplying a main circuit with an electric power from the charger through no battery; a first switch which conducts ON/OFF of supplying the main circuit with the electric power stored in the battery; a second switch which conducts ON/OFF of supplying the main circuit with the electric power through the electric power supplying terminal.
The first and the second switches in the calling apparatus disclosed in Patent Reference 1 are small-sized switches disposed in an operation panel of the calling apparatus, semiconductor switches of which ON/OFF are controlled by the small-sized switches, and the like. Namely, changes of ON/OFF of the first and the second switches are implemented respectively by user's operations.
Patent Reference 1: Official Gazette of unexamined Japanese patent publication H 10-023113